To the 5 and 6 seat aircraft builders:

[Battson]

Of late, we are regularly operating our "4-place" as we originally intended, with three rows of seats and room for 5 or 6 passengers.

Up until recently, the 4-way intercom has been fine, as the youngest member of the family had little to add to the conversation

I am looking for options to extend a 4-way intercom to accommodate either 5 or 6 pairs of headset jacks. Any recommendations - what have you guys done?

For background, our existing intercom is built into the MGL V6 COM radio, so I assume I'll be splicing it into the existing harness somehow. It's a one-plug wonder as far as the headset jacks are concerned.
MGLV6ComRadio-300x226.jpg

By the by, I have seen the 3-way headset adapter / splitter cables. Not interested in having an octopus in the cockpit, I would sooner splice them onto the back of the existing jacks.

[whee]

I’m using a true 6-place intercom. If I were you I’d email Rainier at MGL and see if he will offer a suggestion. He has always been great at helping figure out how to make things work with MGL equipment.

[Bearhawk Aircraft]

On some of these systems you can simply splice into the phone and mic wires for one station, then simply wire another set of jacks. Not possible on all systems but you may give it a try.

[Battson]

I can confirm that this works fine (so far) with the MGL. A very simple solution, thanks!

[500AGL]

At some point the load will add up to a diminished audio and may already sound like a party line. But I understand the value of the mod for now.

Good audio panels are under valued by most pilot/owners. Probably even more so than a a good autopilot. The difference is real.

[Battson]

I can imagine if you daisy chained many headsets it would be bad. With just one additional set of jacks, there was no discernable reduction in quality so far.
But we need to do more testing. Are you aware of any other way to extend an existing intercom? I guess it's not a common requirement, so maybe nobody makes such a product.

[500AGL]

Battson, PS Engineering used to make expansion modules but even they ended that production.
I expect now that 6-place capability is available in most audio panels there are not much demand.

[whee]

I’m reaching back several years so my memory isn’t clear. I know MGL told me the first thing that would be compromised if I expanded the headset jacks beyond the designed 4 is the volume would be reduced on the channel I piggy backed off of. Rainier said something about the mic too but I can’t remember what it was.

In any case, if you’ve already piggybacked one of the channels and the volume is still acceptable then I’d say you are good to go.

MGL does make a 6-place intercom/audio panel. Could change to a V16 com A16 intercom and a single Razor head to run both.

[Battson]

The A16 plus V16 combo with the Razor control panel looks fantastic, vastly superior to what I have. If I was building now, that is what I would have. No question!

Practically though, as much as I already want that upgrade - rewiring an existing aircraft covered in fabric skin, with 6 places, is a hugely invasive task. Especially when the MGL V6 unit I have is wired with limited slack and tucked into a cramped corner of the panel. I doubt the cost and time are worth the reward. I would probably make this kind of upgrade when it's time to recover the fuselage.

[Battson]

I’m reaching back several years so my memory isn’t clear. I know MGL told me the first thing that would be compromised if I expanded the headset jacks beyond the designed 4 is the volume would be reduced on the channel I piggy backed off of. Rainier said something about the mic too but I can’t remember what it was.

In any case, if you’ve already piggybacked one of the channels and the volume is still acceptable then I’d say you are good to go.

That is helpful, thanks Jon. I have checked out those aspects just now. It seems to work pretty well.

For the benefit of future builders, here's some detail:

• I have piggybacked one additional pair of jacks (mic and headphone) onto one of the back seat jack sets, connected at the jacks themselves, so the two pairs of jacks are in series (although the "back seat" is technically now the middle row of seating!). This was done for practical reasons, not because it's ideal. Parallel connections might be better, I can't say.
• The quality of the audio remained the same through all headsets and mics afterwards, or should I say - it's not noticeably different to my ears.
• The intercom mic output coming from the piggybacked pair of jacks (as heard though the other headsets) is practically the same too, no noticeable reduction in volume.
• There could be a minor reduction in the headset volume, coming from the piggybacked headsets, but I have to really use my imagination to hear it. If I am correct, it would be like 5% or something, not 50%.

For all practical intents and purposes, it appears fully functional.